1. Field of the Invention
The present invention relates to a support beam for at least one extended working unit, notably of a paper machine or coater.
2. Description of the Related Art
A support beam for at least one extended working unit is generally known and employed customarily in conjunction with so-called paper machines or coaters. The German Patent Document No. DE 296 00 016, assigned to the assignee of the present invention, e.g., shows a support beam for a long applicator. The applicator rests on the support beam and is designed for direct or indirect application of a liquid or pasty coating medium onto a traveling material web, notably of paper, cardboard or textile material. The applicator can also be designed for final metering of a coating medium applied previously onto the material web. In the so-called direct application, the liquid or pasty coating medium is applied directly onto the surface of the traveling material web, which during application is carried on a revolving countersurface, e.g., an endless belt or a backing roll. In the indirect application of the medium, in contrast, the liquid or pasty coating medium is first applied onto a substrate surface, e.g., the surface of a backing roll configured as an applicator roll. From there, the coating medium is transferred from the applicator roll to the material web in a nip through which the material web passes.
Also known, from German Patent Document No. DE 41 41 133, assigned to the assignee of the present invention, is a support beam which together with a scraper blade forms a so-called scraper. The scraper is also intended for use in a machine for the manufacture or processing of fiber material webs, for example, paper webs. The scraper blade coacts directly with the shell surface of a rotating roll in order to keep the shell surface clean or to lift the paper web off of the shell surface.
In the known designs of the type described above, the support beam is manufactured as a single-piece component and has the shape of a long, hollow element. According to German Patent Document No. DE 41 41 133, e.g., the support beam is a long, hollow element which has a substantially polygonal cross section and is made of a fiber composite material. Instead of making the support beam of fiber composite material, there are also known designs wherein the support beam includes a different material (e.g., steel) and has a round cross-sectional shape.
A difficulty with these known designs, however, is that the support beam is manufactured as a single-piece component and, therefore, can only be configured for a specific load and adapted to particular conditions of use. A modification or reconfiguration of the single-piece support beam for adaptation to different operating conditions, e.g., a wider or narrower paper machine or coater, is normally beyond realization. Instead, the support beam always must be processed as a whole, which requires large and expensive machinery and is associated with high manufacturing costs. For example, employing a support beam in a wide or narrow paper machine or coater requires a dimensioning of the beam cross section in accordance with the loading that is applicable with the machine, for which purpose the cross section of the support beam is changed. Particularly in the manufacture of support beams from fiber composite material, however, a new tool must be made available and used for that purpose. This increases the manufacturing costs further. Special problems are involved particularly when a support beam assumes different temperatures on its front and back, perhaps from the process, e.g., developing heat which radiates from one direction. As a result, one side is heated to a higher temperature, expands, and thereby causes the entire beam to bend.